Fig. 3
TRK1 gene and genes encoding positive/negative regulators of Trk1 activity are determinants of susceptibility/tolerance to formic acid. a Wild-type (wt), trk1Δ and deletion mutants where the genes coding for regulators of Trk1 activity (HAL3, SAT4, HAL5 and PPZ1) were deleted were tested for their susceptibility to formic acid in solid MMB medium (pH 4.5) supplemented with the acid at the indicated concentrations. Resistance (R) and susceptibility (S) phenotypes. b Schematic representation of the positive and negative regulators of Trk1 activity. c Time-course accumulation of [14C]formic acid in non-adapted wild-type cells and trk1Δ cells cultivated in MM4 growth medium (at pH 4.0) after exposure to 30 mM of formic acid during a 45-min period. Values represent the average of at least three independent experiments and the error bars represent the associated standard deviation. The asterisks indicate a significant different (p value <0.05) between the accumulation of [14C]formic acid in wild-type and trk1Δ cells at that time point